Composition for storage battery containers



tion of] Ohio.

COMPOSITION FOR STDRAGE BATTERY' CONTAINERS Edwardrlis. Dilleham GlenaEllymand 0liver' RiesenxOak. Park,.lll., assignors to TheRiehardson. Company, Lockland, Ohio, a. corpora- No Drawing. Application September 13, 1930,

' Somalia-481,801

Our invention relates'to the art-of molding storage battery containers: or boxes" from= compositions comprising a bituminous binder, a mineral. filler," and fibrous matter, usually of vegetableorigin, and ithas .for one of its objects the provisionlof a new and improved type of binder in: such compositions.

More specifically it is an object? of. our: invention .to' provide. a' composition for. storage battery containers;

which contains both: an asphaltic subst'ancemnd as we' shall hereinafter! set a coal tar: pitch, forth. 1

We accomplish? the objects of our invention by that. certain process: and: in that'composition of which we: shall. now describe" an: exemplary embodiment.

It willibe'understoodtthat coal-tar pitches are in general relatively hard at ordinary temperatures, but have ahighsuseeptibility. factor; which means that they shade. on; veryrapidlyupon heating, from asolid. to a liquid" state. They would be advantageous in theimanufacture ofstoragev battery containersfor: several reasons, among which: may be pointedxouti their relative cheapness, .the fact that-they contribute :usefully to the hardness of thecomposition': at ordinary temperatures, and the.-'fa'ct'.' that their'relativei fluidity at higher temperatures may beemployed usefully. to increase the plasticity. of the compound .at molding temperatures.

Howeventhe use of asphaltic substances ini storage battery containers is'desirable by-reason ofthe fact that they do notthaveaahigh sue-- ceptibility factor and shade ofi': comparativelyslowly from a solidstate.toxaliquiistateupon a rise in temperature. Asphaltie substances therefore increase the binder toughness at all temperatures, diminish the: brittlenessof the composition at low temperatures. and.v increase. 401 its resistance. to: distortion at: relatively high Furthermore,- the use of. asphal temperatures.

tic substances may be: employed. to produce in the composition, at mixing temperatures,- a' rela"-= We have discovered that over a comparatively very wide range of asphaltic substances to be mixed with coal tar pitch, precipitation can be avoided by mixing the substances together at such temperatures that the viscosity of the two materials will be substantially the same.

ha-ve-found th'at whencoal tar pitch andasphal tic substances-are mixed together at suhstan-- ti'ally the same viscosity, no trouble is with precipitation. The eifectiveness of ourprocess varies somewhat with diiierent' asphaltic mate-: rials; We have encounteredisolated instances of-asphaltic materialwhich will mix underany; conditions satisfactoril'ywith coaltar pitch, and we have also encountered-isolated instances-of asphaltic material which we havebeen unable 1o satisfactorily to-mix with coal tarpitch and avoid precipitation; but over the general rangei of 'asphaltic materials, we have found? that mixing-at the same viscosity produces ahomogeneousresult and avoids difli'culties with precipitation.

Mixing at the same' vi'scosity may, andusuallydoes iinplytlie-mixingof the asphaltic substance maintained' at one temperature,-- with the coal tar pitch maintained at another. Ihe temperature of the-twosubstances is, of course, .brought 20.:- to the same level by the operation of "the mixing; but 1 the initial, substantially identical viscosity enables the two materials to go together without' difliculty, and the resultant mix is homogeneous; freefr'om precipitation,- and can be'handl'edijust as a singlebinder ma'y be handled.' T

In an exemplary practice; we' employ: as an asphaltic ingredient, a mixture of parts-of an' asphalt known as stanolite with 50'parts of gilsonite: by weight, fluxed together; Afterthe 30;. fluxing operation we maintain this asphaltic binder at atemperature of about 450 Fahrenheit'. The coal tar pitch we maintain (in order that it maybe at thesame viscosity as the asphaltic ingredient) at atemperature of 400 35., Fahrenheit. In makingup a suitablebinder for: storage battery containers, we take'70 parts of the stanolite-gilsonite mixture, having by way of'; example, the-following characteristics:

M. P. 225 F. Pen.'(l50 F.5 se'c.100 gms.)-20.

and holding. it; prior to mixing, at a temperature of 450 Fahrenheit, wethen mix itwith- 30 part's of' coal tar pitch: at a temperatureof- 4-5; 400 Fahrenheit. The pitch may have the following characteristics:

Melting point 220-240.

We manufacture storage battery containers in an exemplary procedure, having a formula comprising 58 parts of combined asphalt and coal tar pitch binder hereinabove described, 30 parts of mineral filler, and 12 parts of fiber. As a mineral filler we prefer to use a diatomaceous earth of acid-resistant character known as Celite. Other mineral fillers are also suitable. They should preferably be acid-resistant their character; and if they. are not porous like diatomaceous earth, they will tend somewhat to increase the specific gravity of the resultant molded composition. We employ as our fibrous ingredient, cotton fibers, such as linters or the like, although other fibers of vegetable or mineral origin may be employed with good results. If the fiber employed is not of acid-resistant character, and if it is of vegetable origin, it should not be employed in amounts greater than 15% by weight of the finished composition. The

minous compositions, a binder forming step comprising the initial maintenance of an asphalt component at a temperature to produce a certain viscosity, and the initial maintenance of a coal tar pitch component at a different temperature, to secure the same viscosity therein, and .the

mixing of the components together while at the' same viscosity.

2. In a process for the manufacture of bituminous compositions, a. binder forming step which comprises mixing together a coal tarpitch component and an asphalt component, the said components being at initially different temperatures, but having substantially the same viscosity. I

3. In a process for the manufacture of bituminous compositions, a binder forming step which comprises mixing together an asphaltic constituent comprising gilsonite and a blown oil, at one temperature, and a coal tar pitch at a different temperature, the temperatures being such that the viscosities of the said components are substantially the same.

4. In a process for making a bituminous composition, the step of mixing together an asphaltic binder component comprising a mixture of stanolite and gilsonite, at about 450 Fahrenheit, and a pitch component at approximately 400 Fahrenheit.

5. A.,process of making a composition for storage battery cases, which comprises blending together 50 parts of stanolite asphalt and 50 parts of gilsonite to produce an asphaltic binder component, and blending said asphaltic binder component with a coal tar pitch binder component in the ratio of 70 parts of the asphaltic component with 30 parts of the coal tar pitch, the said blending being accomplished while the components are at substantially the same viscosity, and mixing with said binder, to the extent of homogeneous distribution, a mineral filler and a fibrous reinforcement.

6. A process of making a composition for storage battery cases, whichcomprises blending together 50 parts of stanolite asphalt and 50 parts of gilsonite to produce an asphaltic binder component, and blending said asphaltic binder component with a coal tar pitch binder component inthe ratio of 70 parts of the asphaltic component with 30 parts of the coal tar pitch, the said blending being accomplished while the components are at substantially the same viscosity, and mixing with saidbinder, to the ex tent of homogeneous distribution, a mineral filler and a fibrous reinforcement, said fibrous material being cotton, and present in amounts not greater than 15% of said composition.

7. A processof making a composition for storage battery cases, which comprises blending together .50 parts of stanolite asphalt and 50 parts of gilsonite to produce an asphaltic binder component, and blending said asphaltic binder component with a coal tar pitch binder component in the ratio of 70 parts of the asphaltic.

component with 30 parts of the coal tar pitch, the said blending being accomplished while the components are at substantially the same .viscosity, and mixing with said binder, to the extent of homogeneous distribution, a mineral filler and a fibrous reinforcement, the said composition comprising 6 parts of binder, 3 parts of mineral filler, and 1 part of cotton fiber.

8. In a process of making plastic bituminous compositions, the steps of controlling the temperature of an asphaltic binder component and controlling the temperature of a coal tar pitch component to bring said components to the same viscosity, and mixing said components together while said compounds have initially the same viscosity.

9. A composition for storage battery containers comprising a mixture of asphalt and coal tar pitch, mineral filler and fibrous reinforcement, the binder component of said composition being characterized as such by more than of both named components, and by homogeneity and an absence of precipitation.

10. A molded product comprising substantially 6 parts by weight of a binder comprising a mixture of coal tar pitch and asphalt, there being present in the mixture as such more than 25% of each component, which mixture is homogeneous in its character and free from precipitation, 3 parts of diatomaceous earth, and 1 part of cotton fiber.

' EDWARD R. DILLEHAY.

.OLIVER O. RIESER. 

